A jetting device for ejecting droplets of a molten metal is known. An example of a jetting device for ejecting droplets of a molten metal is described in WO 2010/063576 A1. In such a printing device, a Lorentz force is generated in the molten metal due to which a droplet is expelled through an orifice of the printing device. Such a device may be used to eject droplets of a molten metal at a high temperature. Hence, using such device, metals having a high melting point, such as silver, gold and copper can be jetted. Direct printing of molten metals may be employed for printing electronic circuitry, for example. In such an application it is essential that all droplets are actually printed accurately as otherwise the electronic circuitry may not function due to an interruption in the electronic connections as a result of a missing droplet, for example. Ejection of a droplet may be hampered in case an orifice is blocked. An orifice that is blocked contains solid material that is deposited in and/or around the orifice. The solid material may comprise e.g. contaminants present in the metal. When an orifice is blocked, it may be more difficult or even impossible to eject a droplet of fluid from the orifice. As a consequence, a decrease in the jetting stability may therefore result in missing droplets. It is therefore desirable to prevent the orifice from becoming blocked.
Therefore, it is an object of the invention to provide a method that prevents blocking of the orifice.